Endoscope camera head

ABSTRACT

An endoscope camera head 6 includes a first and a second members 8, 9 that are relatively rotatable about a first axis Ax1. The first member 8 has a first rotation-sliding surface 84 that extends in an annular shape about the first axis Ax1 as its center. The second member 9 has a second rotation-sliding surface 93 that engages with the first rotation-sliding surface 84 in a state in which movement to a direction of the first axis Ax1 relative to the first member 8 is restricted, and that rotation-slides relative to the first rotation-sliding surface 84 about the first axis Ax1. The second rotation-sliding surface 93 abuts only on a part of the first rotation-sliding surface 84, to expose a part of the first rotation-sliding surface 84 outside.

TECHNICAL FIELD

The present invention relates to an endoscope camera head that is usedin an endoscope device to observe an inside of a subject, such as ahuman body and a mechanical structure.

BACKGROUND ART

Endoscope devices to observe inside a subject, such as a human body anda mechanical structure in a medical field or an industrial field hasconventionally been known (for example, refer to Patent Literature 1).

An endoscope device described in Patent Literature 1 includes anendoscope (optical telescope) that captures and emits a subject imageinside the subject, and an endoscope camera head (TV camera) that holdsthe endoscope and that forms an image from the subject image emittedfrom the endoscope. Moreover, the endoscope is rotatably held about anoptical axis set inside with respect to the endoscope camera head.

Specifically, the endoscope camera head includes a coupler and acamera-head main unit.

The coupler has a bottomed-cylindrical shape in which an eyepiece of theendoscope can be engaged. Furthermore, at a bottom portion of thecoupler, a through hole in a circular shape when viewed from top,piercing therethrough to both sides is formed.

The camera-head main unit includes a casing, and an imaging unit that ishoused in the casing, and that forms an image of the subject imageemitted from the endoscope. On an external surface of the casing, aconcave portion that extends in a ring shape about a first axis as acenter is formed.

Furthermore, the coupler (endoscope) is configured such that a rimportion of the through hole in the coupler engages with the concaveportion of the casing, and that an outer surface of the rim portionslides on an inner surface (hereinafter, referred to as couplerrotation-sliding surface) of the concave portion, thereby rotating withrespect to the camera-head main unit about the first axis as the center.

CITATION LIST Patent Literature

Patent Literature 1: JP-A-2000-227559

DISCLOSURE OF INVENTION Technical Problem

However, in the endoscope camera head described in Patent Literature 1,the coupler rotation-sliding surface is concealed with the casingrotation-sliding surface, and is not exposed outside. Therefore, whencleaning the endoscope camera head, it is difficult to clean a portionbetween the coupler rotation-sliding surface and the casingrotation-sliding surface with a brush. Moreover, it is difficult to letcleaning solution enter between the coupler rotation-sliding surface andthe casing rotation-sliding surface. Accordingly, there is a problemthat much time is consumed for cleaning.

The present invention is achieved in view of the above problem, and itis an object of the present invention to provide an endoscope camerahead that enables to reduce cleaning time.

Solution to Problem

To solve the above-described problem and achieve the object, anendoscope camera head according to the present invention includes afirst member and a second member that are capable of rotating relativeto each other about a first axis, wherein the first member has a firstrotation-sliding surface that extends in an annular shape about thefirst axis as a center, the second member engages with the firstrotation-sliding surface in a state in which movement to a direction ofthe first axis is restricted relative to the first member, and has asecond-rotation sliding surface that rotation-slides relatively to thefirst rotation-sliding surface about the first axis, and the secondrotation-sliding surface abuts only on a part of the firstrotation-sliding surface, to expose a part of the first rotation-slidingsurface outside.

Moreover, in the above-described endoscope camera head according to thepresent invention, in the first member, a concave portion that extendsin an annular shape about the first axis as a center is provided, thefirst rotation-sliding surface includes an inner surface of the concaveportion, in the second member, a convex portion that extends in anannular shape about the first axis as a center, and that engages withthe concave portion is provided, the second rotation-sliding surfaceincludes an outer surface of the convex portion, and at a distal end ofthe convex portion, a groove portion that extends in a spiral shapeabout the first axis as a center, and respective parts of both endportions of which in a direction of the first axis are respectivelypositioned outside the concave portion is formed.

Moreover, in the above-described endoscope camera head according to thepresent invention, in the first member, a concave portion that extendsin an annular shape about the first axis as a center is provided, thefirst rotation-sliding surface includes an inner surface of the concaveportion, in the second member, a projection portion, a distal end ofwhich extends in an arc shape about the first axis as a center, and thatengages with the concave portion is provided, and the secondrotation-sliding surface includes an outer surface of the projectionportion.

Moreover, in the above-described endoscope camera head according to thepresent invention, the projection portion is provided in plurality in adirection of circle about the first axis as a center.

Moreover, the above-described endoscope camera head according to thepresent invention includes: a coupler holding an endoscope that capturesand outputs a subject image; and a camera-head main unit that includes acasing supporting the coupler rotatably about the first axis, and animaging unit that is housed in the casing, and that images the subjectimage emitted from the endoscope, wherein the first member is thecasing, and the second member is the coupler.

Moreover, the above-described endoscope camera head according to thepresent invention includes: a coupler holding an endoscope that capturesand outputs a subject image; and a camera-head main unit that includes acasing supporting the coupler rotatably about the first axis, and animaging unit that is housed in the casing, and that images the subjectimage emitted from the endoscope, wherein the first member is thecoupler, and the second member is the casing.

Advantageous Effects of Invention

In the endoscope camera head according to the present invention, thefirst and the second members constituted of a coupler and a casing,respectively have the first and the second rotation sliding surfaces.The second rotation-sliding surface abuts only on a part of the firstrotation-sliding surface, to expose a part of the first rotation-slidingsurface outside.

Therefore, it is possible to insert a cleaning brush or to let cleaningsolution reach the second rotation-sliding surface through the part ofthe first rotation-sliding surface exposed outside. Furthermore, byrotating the first and the second members relatively to each other aboutthe first axis in a state in which the cleaning brush is inserted or thecleaning solution has entered therein, the first and the secondrotation-sliding surfaces can be easily and efficiently cleaned.

Therefore, according to the endoscope camera head according to thepresent invention, an effect of reducing cleaning time is produced.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating a schematic configuration of anendoscope device according to a first embodiment.

FIG. 2 is a cross-section illustrating a connecting portion between aneyepiece and an endoscope camera head.

FIG. 3 is an enlarged view of a part of FIG. 2.

FIG. 4 is a diagram illustrating a groove portion.

FIG. 5 is a diagram illustrating a modification 1-1 of the firstembodiment.

FIG. 6 is a diagram illustrating the modification 1-1 of the firstembodiment.

FIG. 7 is a cross-section illustrating a connecting portion between aneyepiece and an endoscope camera head according to a second embodiment.

FIG. 8 is a diagram illustrating a coupler according to the secondembodiment.

FIG. 9 is a diagram illustrating an effect of the second embodiment.

FIG. 10 is a diagram illustrating an effect of the second embodiment.

FIG. 11 is a diagram illustrating a modification 2-1 of the secondembodiment.

FIG. 12 is a diagram illustrating the modification 2-1 of the secondembodiment.

FIG. 13 is a diagram illustrating a modification 2-2 of the secondembodiment.

FIG. 14 is a diagram illustrating a modification 2-3 of the secondembodiment.

FIG. 15 is a diagram illustrating a modification 3-1 of the first andthe second embodiments.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, modes (hereinafter, embodiments) to implement the presentinvention will be described with reference to the drawings. Note thatembodiments described below are not intended to limit the presentinvention. Furthermore, like reference symbols are assigned to likeparts in descriptions of the drawings.

First Embodiment

Schematic Configuration of Endoscope Device

FIG. 1 is a diagram illustrating a configuration of an endoscope device1 according to a first embodiment.

The endoscope device 1 is used in a medical field, and is a device totreat a living tissue (incision, and the like) while observing insidethe living body. This endoscope device 1 includes, as illustrated inFIG. 1, a resectscope 2, an endoscope imaging device 3, a display device4, and a control device 5.

The resectscope 2 is a part that is inserted into a living body, andthat captures a subject image and treats a living tissue. Thisresectscope 2 includes, as illustrated in FIG. 1, a sheath 21, a guidetube 22, an endoscope 23, a resect electrode member 24, and a handleportion 25.

The sheath 21 is a part having a cylindrical shape, and inserted into aliving body.

The guide tube 22 has a smaller outer diameter than an inner diameter ofthe sheath 21, and is inserted in the sheath 21. The guide tube 22 isfixed to the sheath 21 through a mounting member 221 (FIG. 1) on itsdistal end side (left side in FIG. 1).

In the mounting member 221, a water supply inlet 222 to infuse solutioninto the sheath 21, and to supply the solution from a distal end of thesheath 21 is provided.

The endoscope 23 is a part of capturing a subject image, and includes,as illustrated in FIG. 1, an insertion portion 231 and an eyepiece 232.

The insertion portion 231 is fixed inside the guide tube 22, and isinserted into the sheath 21. Inside this insertion portion 231, anoptical system that is constituted of one or more lenses, and thatgathers the subject image is provided.

The eyepiece 232 is connected to a proximal end (right end portion inFIG. 1) of the insertion portion 231.

Inside this eyepiece 232, an eyepiece optical system 2321 (refer to FIG.2) that emits the subject image gathered by the optical system insidethe insertion portion 231 from the eyepiece 232 to outside is provided.The eyepiece 232 is formed in a tapered shape in which a diameterincreases toward a right side, and to an increased-diameter portion, theendoscope imaging device 3 is detachably connected.

To the eyepiece 232, a light source connector 2323 to connect a lightguide 2322 is arranged. That is, light supplied to the light guide 2322from a light source device (not shown) is supplied to the insertionportion 231 through the eyepiece 232. The light supplied to theinsertion portion 231 is emitted from the distal end of the insertionportion 231, and is irradiated inside a living body. The lightirradiated inside the living body and reflected in the living body(subject image) is emitted from the eyepiece 232 through the opticalsystem inside the insertion portion 231 and the eyepiece optical system2321.

The resect electrode member 24 is inserted in the sheath 21 through themounting member 221, and its distal end protrudes out from the distalend of the sheath 21. The resect electrode member 24 brought in contactwith a living tissue at its end portion, and treats the living tissuewith a high frequency current.

The handle portion 25 is a part with which a doctor or the like holdsthe resectscope 2, and operates the resect electrode member 24. Thishandle portion 25 includes, as illustrated in FIG. 1, a fixing ring 251,a slider 252, and a spring member 253.

The fixing ring 251 is a part on which a doctor or the like hookshis/her thumb, and is fixed to the guide tube 22.

The slider 252 has the guide tube 22 inserted therethrough, to beconfigured to be movable in a left and right direction in FIG. 1 alongthe guide tube 22.

To this slider 252, the resect electrode member 24 is fixed asillustrated in FIG. 1. That is, the resect electrode member 24reciprocates in a left and right direction in FIG. 1 inside the sheath21, along with movement of the slider 252.

Moreover, in the slider 252, a power source connector 2522 to connect ahigh-frequency power cord 2521 connected to a high frequency powersource (not shown) is provided. This power source connector 2522 iselectrically connected with the resect electrode member 24 through alead (not shown).

Furthermore, in the slider 252, a finger hook member 2523 on whichfingers other than a thumb of a doctor or the like are hooked, to movethe slider 252 (to reciprocate the resect electrode member 24) isarranged.

The spring member 253 has a substantially U-shape, and one end there ofis attached to the fixing ring 251, and the other end is attached to theslider 252. The spring member 253 applies pressure in such a directionthat the slider 252 is apart from the fixing ring 251.

That is, a doctor or the like hooks his/her fingers on the fixing ring251 and the finger hook member 2523, and pulls the finger hook member2523, resisting the pressure of the spring member 253, to thereby movethe slider 252 in rightward in FIG. 1 (to move the resect electrodemember 24 rightward in FIG. 1). On the other hand, when the doctor orthe like moves the fingers off the finger hook member 2523, the slider252 (the resect electrode member 24) moves leftward in FIG. 1 by thepressure of the spring member 253.

The endoscope imaging device 3 is detachably connected to the eyepiece232 of the resectscope 2 (the endoscope 23). The endoscope imagingdevice 3 images a subject image (a subject image emitted from theeyepiece 232) captured by the endoscope 23, and outputs an image signal(RAW signal) from this imaging under control of the control device 5.The image signal is, for example, an image signal of 4K or higher.

A detailed configuration of the endoscope imaging device 3 will bedescribed later.

The display device 4 is constituted of a display using a liquid crystal,an organic EL (electroluminescence), or the like, and displays, under acontrol of the control unit 5, an observation image based on a videosignal from the control unit 5.

The control device 5 includes a (CPU) central processing unit, andcontrols operations of the endoscope imaging device 3, the displaydevice 4, and the light source device (not shown) in a centralizedmanner. For example, the control device 5 generates a video signal fordisplay by subjecting the image signal (RAW signal) output from theendoscope imaging device 3 to predetermined image processing. Thecontrol device 5 then causes the display device 4 to display anobservation image based on the video signal.

Configuration of Endoscope Imaging Device

Next, a configuration of the endoscope imaging device will be described.

FIG. 2 is a cross-section illustrating a connecting portion between theeyepiece 232 and an endoscope camera head 6. FIG. 3 is an enlarged viewof a part of FIG. 2.

The endoscope imaging device 3 includes, as illustrated in FIG. 1 orFIG. 2, the endoscope camera head 6 and a cable 7 (FIG. 1).

The endoscope camera head 6 is a part detachably connected to theeyepiece 232 as illustrated in FIG. 1 or

FIG. 2. This endoscope camera head 6 includes, as illustrated in FIG. 2,a casing 8, a coupler 9, a prism 10, a lens unit 11, and an imaging unit12.

The casing 8 corresponds to a first member according to the presentinvention. This casing 8 includes, as illustrated in FIG. 2 or FIG. 3, acasing main body 81 and an attachment bush 82.

The casing main body 81 is a case that houses the respective parts 10 to12. In this casing main body 81, a protrusion portion 811 in acylindrical shape, communicating inside and outside of the casing mainbody 81 is arranged, as illustrated in FIG. 2 or FIG. 3.

In the protrusion portion 811, as illustrated in FIG. 2 or FIG. 3, ajut-out portion 812 that juts out toward a left side in FIG. 2 and FIG.3 is arranged on an outer circumferential side. This jut-out portion 812has an outer diameter substantially the same as the protrusion portion811, is formed in a cylindrical shape having an inner diameter largerthan the protrusion portion 811, and is integrated with a distal end ofthe protrusion portion 811, coaxially with the protrusion portion 811.Moreover, on an inner circumferential surface of the jut-out portion812, a screw groove 813 is formed.

The attachment bush 82 is a part to attach the coupler 9 to the casing8. This attachment bush 82 includes, as illustrated in FIG. 2 or FIG. 3,a bush main body 821 and a jut-out portion 822.

The bush main body 821 has an inner diameter substantially the same asthe protrusion portion 811, and is formed in a cylindrical shape havingan outer diameter substantially the same as the inner diameter of thejut-out portion 812. Furthermore, on an outer circumferential surface ofthe bush main body 821, a screw groove 823 is formed as illustrated inFIG. 2 or FIG. 3.

The jut-out portion 822 extends out from a rim portion at a left end inFIG. 2, FIG. 3 on the outer circumferential surface of the bush mainbody 821, and is formed in an annular shape having an outer diametersubstantially the same as the jut-out portion 812.

The casing main body 81 and the attachment bush 82 are fixed to eachother, by engaging the screw grooves 813 and 823 with each other. Inthis state, center axes of the casing main body 81 and the attachmentbush 82 agree with each other. The center axis corresponds to a firstaxis Ax1 (FIG. 2, FIG. 3) according to the present invention. Moreover,in the attachment bush 82, an optical device 83 of sapphire glass, orthe like is fixed as illustrated in FIG. 2 or FIG. 3.

In the state in which the casing main body 81 and the attachment bush 82are fixed to each other, with surfaces of respective ends of the jut-outportion 812 and 822 facing each other, and the outer circumferentialsurface of the bush main body 821, a concave portion 84 (FIG. 2, FIG. 3)extending in an annular shape having the first axis Ax1 in center isprovided. An inner surface of the concave portion 84 (the surfaces ofrespective ends of the jut-out portions 812 and 822 facing each other,and the outer circumferential surface of the bush main body 821)corresponds to a first rotation-sliding surface according to the presentinvention.

The coupler 9 is a part corresponding to a second member according tothe present invention. This coupler 9 has a bottomed-cylindrical shapein which the eyepiece 232 can be fitted therein as illustrated in FIG.2.

On an inner circumferential surface of this coupler 9, a pressurizingportion 91 is arranged as illustrate in FIG. 2.

This pressurizing portion 91 has elasticity enable to move in adirection of separation in adjoining isolation relative to a center axisAx2 of the coupler 9, and applies pressure to the eyepiece 232 toward abottom portion of the coupler 9, by abutting on an outer circumferentialsurface of the eyepiece 232 that is fitted in the coupler 9. In thefirst embodiment, four pieces of the pressurizing portions 91 areprovided, and are arranged to be rotationally symmetric at 90° about thecenter axis Ax2. Note that in the state in which the eyepiece 232 isfitted inside the coupler 9, an optical axis Ax3 of the endoscope 23(FIG. 2, hereinafter, referred to as endoscope optical axis Ax3) agreewith the center axis Ax2. Moreover, on an outer circumferential surfaceof the eyepiece 232 on a right end portion in FIG. 2, an expandingportion 2324 that expands toward a right side in FIG. 2 is provided onthe entire circumference. Therefore, when the eyepiece 232 ispressurized toward the bottom portion of the coupler 9 by thepressurizing portion 91, the expanding portion 2324 abuts on the bottomportion. Thus, space Ar (FIG. 2) is formed between the optical device 83and the eyepiece optical system 2321.

Moreover, the bottom portion of the coupler 9 is constituted of a platein a circular shape when viewed from top, each plane of which isperpendicular to the center axis Ax2. Moreover, the bottom portion has athickness substantially the same as a width of the concave portion 84.Furthermore, in the bottom portion, a through hole 92 that penetratesthrough to its front and rear surfaces, and that has a circular shapewhen viewed from top having an inner diameter substantially the same asan outer diameter of the bush main body 821 is formed. The coupler 9 isattached to the casing 8 as a rim portion of the through hole 92 engageswith (fits in) the concave portion 84 in a state in which an opening ofthe bottomed-cylindrical shape is directed to the left side in FIG. 2.In this state, the center axis Ax2 agrees with the first axis Ax1.Moreover, the coupler 9 is restricted its movement to a direction of thefirst axis Ax1 relative to the casing 8, and is rotatable relative tothe casing 8 about the first axis Ax1 (the center axis Ax2).

Therefore, the endoscope camera head 6 is structured rotatable about thefirst axis Ax1 (the center axis Ax2, the endoscope optical axis Ax3),relative to the eyepiece 232 of the endoscope 23 through the coupler 9.Moreover, the endoscope camera head 6 is structured such that its centerof gravity O (FIG. 1) is positioned off the first axis Ax1 (a rotationcenter axis relative to the eyepiece 232). The endoscope camera head 6rotates about the first axis Ax1 irrespective of rotation about thefirst axis Ax1 of the resectscope 2, and is structured to maintain anorientation in which an optical axis Ax4 (FIG. 2, hereinafter, referredto as in-case optical axis Ax4) set inside the casing 81 is along avertical direction (orientation in which the center of gravity O ispositioned below the first axis Ax1) all the time.

The rim portion of the through hole 92 extends in an annular shape aboutthe first axis Ax1, and corresponds to a convex portion 93 (FIG. 2, FIG.3) according to the present invention. Furthermore, the outer surface ofthe convex portion 93 is a portion that slides on the inner surface ofthe concave portion 84, and corresponds to a second rotation-slidingsurface according to the present invention.

At a distal end of the convex portion 93 (inner surface of the throughhole 92), a groove portion 94 is formed as illustrated in FIG. 2 or FIG.3.

FIG. 4 is a diagram illustrating the groove portion 94. The grooveportion 94 extends in a spiral shape about the first axis Ax1 (thecenter axis Ax2) at the distal end of the convex portion 93 asillustrated in FIG. 4. In the state in which the coupler 9 is attachedto the casing 8, a part of both end portions 941, 942 in the directionof the first axis Ax1 in the groove portion 94 is respectivelypositioned outside the concave portion 84.

That is, in the state in which relative rotation of the casing 8 and thecoupler 9 about the first axis Ax1 is stopped, the outer surface of theconvex portion 93 (the second rotation-sliding surface according to thesecond embodiment) abuts only on a part of the inner surface (the firstrotation-sliding surface according to the present invention) of theconcave portion 84 by having the groove portion 94, enabling to expose apart of the inner surface of the concave portion 84 outside.

The prism 10 is arranged on the first axis Ax1 and on the in-caseoptical axis Ax4 as illustrated in FIG. 2, and polarizes a subject imagecaptured by the endoscope 23 to change the traveling direction.Specifically, the prism 10 polarizes a subject image (subject image thattravels along the endoscope optical axis Ax3) that is emitted from theeyepiece 232 and taken into the casing 8 through the optical device 83,to change the traveling direction by 90° to travel along the in-caseoptical axis

Ax4.

The lens unit 11 is arranged on the in-case optical axis Ax4 asillustrated in FIG. 2. This lens unit 11 is constituted of one or plurallenses, and forms an image of the subject image entering through theprism 10 on an imaging surface of the imaging unit 12. Moreover, thelens unit 11 is provided with an optical zoom function (not shown) thatchanges an angle of view by moving the one or plural lenses undercontrol of the control device 5 or an operating unit 13 (FIG. 1), and afocus mechanism (not shown) that changes a focal point.

The imaging unit 12 is arranged on the in-case optical axis Ax4 asillustrated in FIG. 2. The imaging unit 12 images a subject image formedby the lens unit 11 under control of the control device 5. This imagingunit 12 is constituted of a sensor chip in which an imaging device (notshown) that receives a subject image formed by the lens unit 11 toconvert into an electrical signal, such as a CCD (charge coupled device)and a CMOS (complementary metal oxide semiconductor), and a signalprocessing unit (not shown) that outputs an image signal by subjectingthe electrical signal (analog signal) from the imaging device to asignal processing (A/D conversion, and the like), and the like areintegrally formed, and outputs the image signal (RAW signal (digitalsignal)) subjected to the A/D conversion. Note that the signalprocessing unit described above may be prepared as a separate unitwithout integrating with the imaging device.

The cable 7 is detachably connected at its one end to the control device5 through a connector CN1 (FIG. 1), and is detachably connected at theother end to the endoscope camera head 6 through a connector CN2 (FIG.1). The cable 7 transmits an image signal output from the endoscopecamera head 6 to the control device 5, and transmits a control signal, asynchronization signal, a clock, power, and the like output from thecontrol device 5 to the endoscope camera head 6.

Note that in transmission of an image signal from the endoscope camerahead 6 through the cable 7, the image signal may be transmitted in anoptical signal, or may be transmitted in an electrical signal. The sameapplies to transmission of the control signal, the synchronizationsignal, and the clock from the control device 5 to the endoscope camerahead 6 through the cable 7.

Moreover, in the cable 7, the operating unit 13 that receives variouskinds of operations from a doctor and the like (for example, aninstruction of image quality adjustment (white balance adjustment,brightness adjustment, and the like) of an observation image, aninstruction to change an angle of view or a focal point of the lens unit11, and the like) is provided as illustrated in FIG. 1.

According to the first embodiment described above, following effects areproduced.

The endoscope camera head 6 according to the first embodiment includesthe casing 8 having the concave portion 84 that extends in an annularshape about the first axis Ax1, and the coupler 9 having the convexportion 93 that extends in an annular shape about the first axis Ax1 andthat engages with the concave portion 84. Moreover, at the distal end ofthe convex portion 93, the groove portion 94 is formed that extends in aspiral shape about the first axis Ax1, and in which respective parts ofthe both end portions 941 and 942 in the direction of the first axis Ax1are positioned outside the concave portion 84, respectively. The outersurface of the convex portion 93 abuts only on a part of the innersurface of the concave portion 84 by having the groove portion 94, inthe state in which relative rotation of casing 8 and the coupler aboutthe first axis Ax1 is stopped, to expose a part of the inner surface ofthe concave portion 84.

Therefore, by relatively rotating the casing 8 and the coupler 9 aboutthe first axis Ax1 in a state in which the endoscope camera head 6 isimmersed in cleaning solution, the cleaning solution flows into thegroove portion 94 from the end portion 941 as indicated by an arrow inFIG. 3, and follows the groove portion 94 to flows out of the grooveportion 94 from the end portion 942. That is, it is possible to clean aportion between the inner surface of the concave portion 84 and theouter surface of the convex portion 93 easily and effectively. Note thatdepending on a rotation direction of the casing 8 and the coupler 9, aflowing direction of the cleaning solution indicated by the arrow inFIG. 3 is to be opposite.

Therefore, according to the endoscope camera head 6 according to thefirst embodiment, an effect of reducing the cleaning time is produced.

Modification 1-1 of First Embodiment

FIG. 5 and FIG. 6 are diagrams illustrating a modification 1-1 of thefirst embodiment. Specifically, FIG. 5 is a diagram corresponding toFIG. 3. FIG. 6 is a diagram illustrating a groove portion 815 accordingto the modification 1-1.

In the endoscope camera head 6 according to the first embodimentdescribed above, the first member according to the present invention isthe casing 8, and the second member according to the present inventionis the coupler 9, but it is not limited thereto. For example, as anendoscope camera head 6A according to the modification 1-1 illustratedin FIG. 5 and FIG. 6, the first member according to the presentinvention may be a coupler 9A, and the second member according to thepresent invention may be a casing 8A.

Specifically, the coupler 9A according to the modification 1-1 includesa coupler main body 95 and an attachment bush 96 as illustrated in FIG.5.

The coupler main body 95 has a bottomed-cylindrical shape enabling to beengaged in the eyepiece 232, similarly to the coupler 9 described in thefirst embodiment.

In a bottom portion of this coupler main body 95, a through hole 951that penetrates through to its front and rear surfaces, and that has acircular shape when viewed from top is formed as illustrated in FIG. 5.Moreover, on an inner circumferential surface of the through hole 951, ajut-out portion 952 that extends toward the center axis Ax2 and that hasan annular shape around the center axis Ax2 as its center is formed on aright end rim side in FIG. 5. Furthermore, on the inner circumferentialsurface of the through hole 951, a screw groove 953 is formed on a leftside in FIG. 5 relative to the jut-out portion 952.

The attachment bush 96 is a member to attach the coupler 9A to thecasing 8A. This attachment bush 96 includes a bush main body 961 and ajut-out portion 962 as illustrated in FIG. 5.

The bush main body 961 has an outer diameter substantially the same asan inner diameter of the through hole 951, and is formed in acylindrical shape having an inner diameter larger than the innerdiameter of the jut-out portion 952. Moreover, on an outercircumferential surface of the bush main body 961, a screw groove 963 isformed as illustrated in FIG. 5.

The jut-out portion 962 protrudes toward the center axis Ax2 from a leftend rim side of an inner circumferential surface of the bush main body961 in FIG. 1, and is formed in an annular shape having an innerdiameter substantially the same as the jut-out portion 952.

The coupler main body 95 and the attachment bush 96 are fixed to eachother, by engaging the screw grooves 953 and 963 with each other. Inthis state, a center axis of the attachment bush 96 agrees with thecenter axis Ax2 of the coupler main body 95.

In the state in which the coupler main body 95 and the attachment bush96 are fixed to each other, with surfaces of respective ends of thejut-out portions 952 and 962 facing each other, and the innercircumferential surface of the bush main body 961, a concave portion 97extending in an annular shape having the first axis Ax1 in center isprovided as illustrated in FIG. 5. An inner surface of the concaveportion 97 (the surfaces of respective ends of the jut-out portions 952and 962 facing each other, and the inner circumferential surface of thebush main body 961) corresponds to the first rotation-sliding surfaceaccording to the present invention.

Moreover, the casing 8A according to the modification 1-1 is structuredwithout the attachment bush 82, omitting from the casing 8 described inthe first embodiment above, and is constituted of only of the casing 81Ahaving a protrusion portion 811A in a different shape from theprotrusion portion 811.

The protrusion portion 811A has a bottomed-cylindrical shape thatcommunicates inside and outside of the casing main body 81A, similarlyto the protrusion portion 811 described in the first embodiment.Moreover, in the protrusion portion 811A, the optical device 83 is fixedas illustrated in FIG. 5. Furthermore, in the protrusion portion 811A, aconvex portion 814 that protrudes out from the left end rim on the outercircumferential surface in FIG. 5, and that has an annular shape havingthe first axis Ax1 as its center is provided. This convex portion 814has thickness substantially the same as a width of the concave portion97. Moreover, the convex portion 814 has an outer diameter substantiallythe same as the inner diameter of the bush main body 961. The coupler 9Ais attached to the casing 8A as the convex portion 814 engages with(fits in) the concave portion 97. In this state, the center axis Ax2agrees with the first axis Ax1. Moreover, the coupler 9A is restrictedits movement to a direction of the first axis Ax1 relative to the casing8A, and is rotatable relative to the casing 8A about the first axis Ax1(the center axis Ax2).

The outer surface of the convex portion 814 is a portion that slides onthe inner surface of the concave portion 97, and corresponds to thesecond rotation-sliding surface according to the present invention.

At a distal end of the convex portion 814, a groove portion 815 isformed as illustrated in FIG. 5 or FIG. 6.

The groove portion 815 extends in a spiral shape about the first axisAx1 at the distal end of the convex portion 814 as illustrated in FIG.6. In the state in which the coupler 9A is attached to the casing 8A,respective parts of the both end portions 816 and 817 in the directionof the first axis Ax1 in the groove portion 815 are positioned outsidethe concave portion 97, respectively.

That is, the outer surface of the convex portion 814 (the secondrotation-sliding surface according to the present invention) abuts onlyon a part of the inner surface of the concave portion 97 (the firstrotation-sliding surface according to the present invention) by havingthe groove portion 815, in the state in which relative rotation ofcasing 8 and the coupler 9A about the first axis Ax1 is stopped, toexpose a part of the inner surface of the concave portion 97.

As the modification 1-1 described above, also when the first memberaccording to the present invention is the coupler 9A, and the secondmember according to the present invention is the casing 8A, effectssimilar to those of the first embodiment described above are produced.

Second Embodiment

Next, a second embodiment of the present invention will be described.

Hereinafter, same reference symbols are assigned to same components asthe first embodiment described above, and detailed description thereofis omitted or simplified.

FIG. 7 is a cross-section illustrating a connecting portion between theeyepiece 232 and an endoscope camera head 6B according to the secondembodiment. FIG. 8 is a diagram illustrating a coupler 9B according tothe second embodiment. Specifically, FIG. 8 is a diagram of a view ofthe coupler 9B from a side on which the eyepiece 232 is fitted in.

In the endoscope camera head 6B according to the second embodiment, asillustrated in FIG. 7 or FIG. 8, the coupler 9B in a different shapefrom the coupler 9 is used for the endoscope camera head 6 described inthe first embodiment above.

The coupler 9B has a through hole 92B having an inner diameter largerthan the inner diameter of the through hole 92 when compared with thecoupler 9 described in the first embodiment. The inner diameter of thisthrough hole 92B is set to be larger than the outer diameter of thejut-out portions 812, 822. Moreover, on an inner circumferential surfaceof the through hole 92B, a projection portion 98 that projects towardthe center axis Ax2 from a right end rim side in FIG. 7, and in which aproximal end thereof extends in an arc shape having the center axis Ax2(the first axis Ax1) as its center is formed. This projection portion 98has thickness substantially the same as the width of the concave portion84. In the second embodiment, three pieces of the projection portions 98are provided, and are arranged to be rotationally symmetric at 120°about the center axis Ax2 (the first axis Ax1). Furthermore, a locus ofdistal ends of the three projection portion 98 forms a circular shapehaving a diameter substantially the same as the outer diameter of thebush main body 821. The coupler 9B is attached to the casing 8 as thethree projection portions 98 respectively engage with (fit in) theconcave portion 84 in a state in which an opening of thebottomed-cylindrical shape is directed to the left side in FIG. 7. Inthis state, the center axis Ax2 agrees with the first axis Ax1.Moreover, the coupler 9B is restricted its movement to a direction ofthe first axis Ax1 relative to the casing 8, and is rotatable relativeto the casing 8 about the first axis Ax1 (the center axis Ax2).

The outer surface of the projection portion 98 is a portion that slideson the inner surface of the concave portion 84, and corresponds to thesecond rotation-sliding surface according to the present invention.

That is, the outer surface of the projection portion 98 (the secondrotation-sliding surface according to the present invention) abuts onlyon a part of the inner surface (the first rotation-sliding surfaceaccording to the present invention) of the concave portion 84 in a statein which relative rotation of the casing 8 and the coupler 9B about thefirst axis Ax1 is stopped, to expose a part of the inner surface of theconcave portion 84.

According to the second embodiment described above, following effectsare produced.

FIG. 9 and FIG. 10 are diagrams illustrating an effect of the secondembodiment. Specifically, FIG. 9 is a diagram corresponding to FIG. 7.FIG. 10 is a diagram corresponding to FIG. 8.

The endoscope camera head 6B according to the second embodiment includesthe casing 8 having the concave portion 84 that extends in an annularshape having the first axis Ax1 as its center, and the coupler 9B havingthe projection portion 98, the distal end of which extends in an arcshape having the first axis Ax1 as its center and engages with theconcave portion 84. The outer surface of the projection portion 98 abutsonly on a part of the inner surface of the concave portion 84 in a statein which relative rotation of the casing 8 and the coupler 9B about thefirst axis Ax1 is stopped, to expose a part of the inner surface of theconcave portion 84 outside.

Therefore, the inner surface of the concave portion 84 can be cleaned asdescribed below.

That is, as illustrated in FIG. 9 or FIG. 10, in a gap between a rimportion of the through hole 92B and the jut-out portion 812, a cleaningbrush Br is brought into contact with the inner surface of the concaveportion 84 from a portion at which the projection portion 98 is notformed. By rotating the coupler 9B and the cleaning brush Br about thefirst axis Ax1 with respect to the casing 8 as indicated by an arrow inFIG. 10, a portion between the inner surface of the concave portion 84and the outer surface of the projection portion 98 can be cleaned easilyand efficiently.

Therefore, according to the endoscope camera head 6B according to thesecond embodiment, an effect of reducing cleaning time is produced.

Moreover, in the gap between the rim portion of the through hole 92B andthe jut-out portion 812, a portion at which the projection portion 98 isnot formed is to be a ventilation hole that communicates inside andoutside a space Ar. For this, it is possible to suppress formation ofcondensation on the eyepiece optical system 2321 or the optical device83, and to reduce drying time when condensation is formed.

Particularly, three pieces of the projection portions 98 are provided atpositions to be rotationally symmetric at 120° about the first axis Ax1.For this, the ventilation holes that communicate inside and outside thespace Ar can be spaced uniformly, and it is possible to suppressformation of condensation on the eyepiece optical system 2321 and theoptical device 83 effectively, and to significantly reduce drying timewhen condensation is formed.

Modification 2-1 of Second Embodiment

FIG. 11 and FIG. 12 are diagrams illustrating a modification 2-1 of thesecond embodiment. Specifically, FIG. 11 is a cross section illustratinga connecting portion between a casing 8C and the coupler 9A according tothe modification 2-1. FIG. 12 is a view of the casing 8C from a distalend side of a protrusion portion 811C.

In the endoscope camera head 6B according to the second embodimentdescribed above, the first member according to the present invention isthe casing 8, and the second member according to the present inventionis the coupler 9B, but it is not limited thereto. For example, as anendoscope camera head 6C according to the modification 2-1 illustratedin FIG. 11 and FIG. 12, the first member according to the presentinvention may be the coupler 9A, and the second member according to thepresent invention is the casing 8C.

Specifically, the coupler 9A according to the modification 2-1 has thesame configuration as the coupler 9A described in the modification 1-1.

Moreover, the casing 8C according to the modification 2-1 is structuredwithout the attachment bush 82, omitting from the casing 8 described inthe second embodiment, and is constituted of only of a casing main body81C having the protrusion portion 811C in a different shape from theprotrusion portion 811 as illustrated in FIG. 11 or FIG. 12.

The protrusion portion 811C has a cylindrical shape that communicatesinside and outside the casing main body 81C, similarly to the protrusionportion 811 described in the second embodiment. Moreover, inside theprotrusion portion 811C, the optical device 83 is fixed as illustratedin FIG. 11. Furthermore, in the protrusion portion 811C, a projectionportion 818 that protrudes from a left end rim side in FIG. 11 on anouter surface, and a proximal end of which extends in an arc shapehaving the first axis Ax1 as its center is formed. This projectionportion 818 has thickness substantially the same as the width of theconcave portion 97. In the modification 2-1, three pieces of theprojection portions 818 are provided, and are arranged to berotationally symmetric at 120° about the first axis Ax1. Furthermore, alocus of distal ends of the three projection portions 98 forms acircular shape having a diameter substantially the same as the innerdiameter of the bush main body 961. The coupler 9A is attached to thecasing 8C as the three projection portions 818 respectively engage with(fit in) the concave portion 97 in a state in which an opening of thebottomed-cylindrical shape is directed to the left side in FIG. 11. Inthis state, the center axis Ax2 agrees with the first axis Ax1.Moreover, the coupler 9C is restricted its movement to a direction ofthe first axis Ax1 relative to the casing 8C, and is rotatable relativeto the casing 8C about the first axis Ax1 (the center axis Ax2).

The outer surface of the projection portion 818 is a portion that slideson the inner surface of the concave portion 97, and corresponds to thesecond rotation-sliding surface according to the present invention.

That is, the outer surface of the projection portion 818 (the secondrotation-sliding surface according to the present invention) abuts onlyon a part of the inner surface of the concave portion 97 (the firstrotation-sliding surface according to the present invention), in thestate in which relative rotation of casing 8C and the coupler 9A aboutthe first axis Ax1 is stopped, to expose a part of the inner surface ofthe concave portion 97.

As in the modification 2-1 described above, also when the first memberaccording to the present invention is the coupler 9A, and the secondmember according to the present invention is the casing 8C, a similareffect as the second embodiment described above is produced.

Modification 2-2 of Second Embodiment

FIG. 13 is a diagram illustrating a modification 2-2 of the secondembodiment. Specifically, FIG. 13 is a diagram corresponding to FIG. 7.

In the second embodiment described above, a projection portion 98D maybe used instead of the projection portion 98 as in an endoscope camerahead 6D (coupler 9D) according to the modification 2-2 illustrated inFIG. 13.

The projection portion 98D includes a projection-portion main body 981and a convex portion 982 as illustrated in FIG. 13.

The projection-portion main body 981 is a portion that protrudes towardthe center axis Ax2 from a right end rim side in FIG. 13 on the innercircumferential surface of the through hole 92B. A proximal end of thisprojection-portion main body 981 extends in an arc shape having thecenter axis Ax2 (the first axis Ax1) as its center. Moreover, theprojection-portion main body 981 has thickness larger than the width ofthe concave portion 84. Furthermore, a locus of distal ends of the threeprojection portions 981 forms a circular shape having a diametersubstantially the same as the outer diameter of the jut-out portion 812

The convex portion 982 protrudes toward the center axis Ax2 from a leftend rim side in FIG. 13 at the distal end of the projection-portion mainbody 981. This convex portion 982 has thickness substantially the sameas the width of the concave portion 84. Moreover, a locus of distal endsof the three convex portions 982 forms a circular shape having adiameter smaller than the outer diameter of the jut-out portion 812, andlarger than the outer diameter of the bush main body 821.

As described above, the distal end of the projection portion 98D isformed in a stepped-shape along the center axis Ax2 by the convexportion 982.

With the structure described above, the coupler 9D is attached to thecasing 8 as the three convex portions 982 respectively engage with (fitin) the concave portion 84 in a state in which an opening of thebottomed-cylindrical shape is directed to a left side in FIG. 13, and asthe distal end of the projection-portion main body 981 abuts on theouter circumferential surface of the jut-out portion 812. In this state,the center axis Ax2 agrees with the first axis Ax1. Moreover, thecoupler 9D is restricted its movement to the direction of the first axisAx1 relative to the casing 8, and is rotatable relative to the casing 8about the first axis Ax1 (the center axis Ax2).

The inner surface of the concave portion 84 and the outercircumferential surface and the jut-out portion 812 are portions onwhich the coupler 9D slides, and corresponds to the firstrotation-sliding surface according to the present invention. Moreover,the outer surface of the projection portion 98D (the distal end of theprojection-portion main body 981 and the outer surface of the convexportion 982) is a portion that slides on the inner surface of theconcave portion 84 and on the outer circumferential surface of thejut-out portion 812, and corresponds to the second rotation-slidingsurface according to the present invention.

That is, the outer surface of the projection portion 98D (the secondrotation-sliding surface according to the present invention) abuts onlyon a part of the inner surface of the concave portion 84 and of theouter circumferential surface of the jut-out portion 812 (the firstrotation-sliding surface according to the present invention) in a statein which relative rotation of the casing 8 and the coupler 9D about thefirst axis Ax1 is stopped, to expose a part of the inner surface of theconcave portion 84 and of the outer circumferential surface of thejut-out portion 812 outside.

According to the modification 2-2 described above, in addition to theeffect similar to the second embodiment described above, a followingeffect is produced.

In the endoscope camera head 6D according to the modification 2-2, theouter circumferential surface of the jut-out portion 812 and the distalend of the projection-portion main body 981 form a part of the first andthe second rotation-sliding surfaces according to the present invention.That is, not a portion deep inside, but a portion easy to clean forms apart of the first and the second rotation-sliding surfaces according tothe present invention. Therefore, cleaning is made further easier, andcleaning time can be further reduced.

Modification 2-3 of Second Embodiment

FIG. 14 is a diagram illustrating a modification 2-3 of the secondembodiment. Specifically, FIG. 14 is a diagram corresponding to FIG. 7.

In the second embodiment described above, as in an endoscope camera headBE (coupler 9E) according to the modification 2-3 illustrated in FIG.14, a projection portion 98E may be used instead of the projectionportion 98.

The projection portion 98E is arranged at a position offset to rightside (side apart from the eyepiece 232) from the projection portion 98described in the second embodiment.

According to the modification 2-3 described above, in addition to aneffect similar to the second embodiment, a following effect is produced.

In the endoscope camera head 6E according to the modification 2-3, theprojection portion 98E is arranged at a position offset to a directionapart from the eyepiece 232. That is, by expanding the space Ar,sufficient ventilation is achieved. Therefore, it is possible tosuppress formation of condensation on the eyepiece optical system 2321or the optical device 83 effectively, and to significantly reduce dryingtime when condensation is formed.

Other Embodiments

Embodiments to implement the present invention have been described, butthe present invention is not limited only to the first and the secondembodiments and the modifications 1-1, 2-1 to 2-3 described above.

FIG. 15 is a diagram illustrating a modification 3-1 of the first andthe second embodiments.

In the first and the second embodiments and the modifications 1-1, 2-1to 2-3, the endoscope camera heads 6, 6A to 6E are detachably providedwith respect to the resectscope 2 for urinary organs, but it is notlimited thereto. As in an endoscope device 1F according to themodification 3-1 illustrated in FIG. 15, the endoscope camera head 6 maybe detachably provided, for example, with respect to an endoscope 2F fordigestive organs.

The endoscope 2F is constituted of a rigid endoscope. That is, theendoscope 2F is hard or at least a part thereof is flexible and has athin and long shape, to be inserted into a living body. In thisendoscope 2F, an optical system that is constituted of one or morelenses, and gathers a subject image is provided. Light supplied from alight source device 14 (FIG. 15) to the light guide 2322 is emitted froma distal end of the endoscope 2F, to be irradiated to an inside of theliving body. The light irradiated inside the living body and reflectedinside the living body (subject image) is gathered by the optical systemin the endoscope 2F. The endoscope camera head 6 images the subjectimage gathered by the optical system in the endoscope 2F.

Moreover, not limited to a rigid endoscope, the endoscope 2F may be aflexible endoscope.

In the first and the second embodiments, and the modifications 1-1, 2-1to 2-3, 3-1, the endoscope devices 1, 1F may be an endoscope device thatis used in an industrial field, and that observes inside a subject, suchas a mechanical structure.

In the first embodiment and the modification 1-1 described above, thegrooves according to the present invention (the groove portions 94, 815)are arranged in the convex portions 93, 814, but it is not limitedthereto, and may be arranged in the concave portions 84, 97.

In the second embodiment and the modifications 2-1 to 2-3 describedabove, the number of the projection portions according to the presentinvention (the projection portions 98, 98D, 98E, 818) is not limited tothree, but may be one, two, four, or more.

REFERENCE SIGNS LIST

-   -   1, 1F ENDOSCOPE DEVICE    -   2 RESECTSCOPE    -   2F ENDOSCOPE    -   3 ENDOSCOPE IMAGING DEVICE    -   4 DISPLAY DEVICE    -   5 CONTROL DEVICE    -   6, 6A TO 6E ENDOSCOPE CAMERA HEAD    -   7 CABLE    -   8, 8A, 8C CASING    -   9, 9A, 9B, 9D COUPLER    -   10 PRISM    -   11 LENS UNIT    -   12 IMAGING UNIT    -   13 OPERATING UNIT    -   14 LIGHT SOURCE DEVICE    -   21 SHEATH    -   22 GUIDE TUBE    -   23 ENDOSCOPE    -   24 RESECT ELECTRODE MEMBER    -   25 HANDLE PORTION    -   81, 81A, 81C CASING MAIN BODY    -   82 ATTACHMENT BUSH    -   83 OPTICAL DEVICE    -   84 CONCAVE PORTION    -   91 PRESSURIZING PORTION    -   92, 92B THROUGH HOLE    -   93 CONVEX PORTION    -   94 GROOVE PORTION    -   95 COUPLER MAIN BODY    -   96 ATTACHMENT BUSH    -   97 CONCAVE PORTION    -   98, 98D, 98E PROJECTION PORTION    -   221 MOUNTING MEMBER    -   222 WATER SUPPLY INLET    -   231 INSERTION PORTION    -   232 EYEPIECE    -   251 FIXING RING    -   252 SLIDER    -   253 SPRING MEMBER    -   811, 811A, 811C PROTRUSION PORTION    -   812 JUT-OUT PORTION    -   813 SCREW GROOVE    -   814 CONVEX PORTION    -   815 GROOVE PORTION    -   816, 817 BOTH END PORTION    -   818 PROJECTION PORTION    -   821 BUSH MAIN BODY    -   822 JUT-OUT PORTION    -   823 SCREW GROOVE    -   941, 942 BOTH END PORTION    -   951 THROUGH HOLE    -   952 JUT-OUT PORTION    -   953 SCREW GROOVE    -   961 BUSH MAIN BODY    -   962 JUT-OUT PORTION    -   963 SCREW GROOVE    -   981 PROJECTION-PORTION MAIN BODY    -   982 CONVEX PORTION    -   2321 EYEPIECE OPTICAL SYSTEM    -   2322 LIGHT GUIDE    -   2323 LIGHT SOURCE CONNECTOR    -   2324 EXPANDING PORTION    -   2521 HIGH-FREQUENCY POWER CORD    -   2522 POWER SOURCE CONNECTOR    -   2523 FINGER HOOK MEMBER    -   Ar SPACE    -   Ax1 FIRST AXIS    -   Ax2 CENTER AXIS    -   Ax3 ENDOSCOPE OPTICAL AXIS    -   Ax4 IN-CASE OPTICAL AXIS    -   CN1, CN2 CONNECTOR    -   O CENTER OF GRAVITY

1. An endoscope camera head comprising a first member and a secondmember that are capable of rotating relative to each other about a firstaxis, wherein the first member has a first rotation-sliding surface thatextends in an annular shape about the first axis as a center, the secondmember engages with the first rotation-sliding surface in a state inwhich movement to a direction of the first axis is restricted relativeto the first member, and has a second-rotation sliding surface thatrotation-slides relatively to the first rotation-sliding surface aboutthe first axis, and the second rotation-sliding surface abuts only on apart of the first rotation-sliding surface, to expose a part of thefirst rotation-sliding surface outside.
 2. The endoscope camera headaccording to claim 1, wherein in the first member, a concave portionthat extends in an annular shape about the first axis as a center isprovided, the first rotation-sliding surface includes an inner surfaceof the concave portion, in the second member, a convex portion thatextends in an annular shape about the first axis as a center, and thatengages with the concave portion is provided, the secondrotation-sliding surface includes an outer surface of the convexportion, and at a distal end of the convex portion, a groove portionthat extends in a spiral shape about the first axis as a center, andrespective parts of both end portions of which in a direction of thefirst axis are respectively positioned outside the concave portion isformed.
 3. The endoscope camera head according to claim 1, wherein inthe first member, a concave portion that extends in an annular shapeabout the first axis as a center is provided, the first rotation-slidingsurface includes an inner surface of the concave portion, in the secondmember, a projection portion, a distal end of which extends in an arcshape about the first axis as a center, and that engages with theconcave portion is provided, and the second rotation-sliding surfaceincludes an outer surface of the projection portion.
 4. The endoscopecamera head according to claim 3, wherein the projection portion isprovided in plurality in a direction of circle about the first axis as acenter.
 5. The endoscope camera head according to claim 1, comprising: acoupler holding an endoscope that captures and outputs a subject image;and a camera-head main unit that includes a casing supporting thecoupler rotatably about the first axis, and an imaging unit that ishoused in the casing, and that images the subject image emitted from theendoscope, wherein the first member is the casing, and the second memberis the coupler.
 6. The endoscope camera head according to claim 1,comprising: a coupler holding an endoscope that captures and outputs asubject image; and a camera-head main unit that includes a casingsupporting the coupler rotatably about the first axis, and an imagingunit that is housed in the casing, and that images the subject imageemitted from the endoscope, wherein the first member is the coupler, andthe second member is the casing.